This invention relates to an adjustable ring light and more particularly to an adjustable ring light capable of changing the angle of incidence of the light beams so as to permit concentrating the light on a subject which is moved without having to move the light sources.
There are a variety of situations where it is necessary to concentrate multiple beams from a light holder (i.e., a ring light) to insure adequate lighting conditions, such as an object being examined under a microscope or in an operating room during the conduct of a surgical procedure in a confined location.
At the present time the concentration of light is usually accomplished by mounting multiple sources of light in a fixture such as a ring light with the light beams coming together at a point. Typically the fixture itself is mounted so as to permit its movement in order to concentrate the multiple sources of light on the object or location where required.
Mountings which are designed to accomplish this are usually complex and sometimes cumbersome to use, and generally occupy considerable space, whereas in many situations the space available is quite limited and not completely adequate or suitable for such a mounting.
A variety of U.S. patents have been issued which illustrate earlier efforts to permit the concentration of multiple light beams on a work area. In U.S. Pat. Nos. 3,360,640 and 3,437,803 are shown universal type mountings. U.S. Pat. Nos. 3,500,054 and 3,806,256 described arrangements in which the light sources are mounted on a movable frame. In U.S. Pat. No. 3,786,243 a swivel joint is employed, and in U.S. Pat. No. 4,447,114 a rotational configuration is described.